In igniting pyrotechnic propellants for explosively inflating a gas bag, gaseous combustion products materialize having very high temperatures which the material of the gas bag, consisting of a synthetic textile fabric, is unable to withstand. Accordingly, various proposals have already been made as to how gas bags of air bag modules may be configured and arranged so that they cannot be damaged or even destroyed by the hot combustion gases. Such means are termed "flame protection" and extend from sieve-type retaining systems intended to prevent the exit of hot solid particles from the inflator, via localized material doubling in the endangered region up to impregnating the gas bag all over with a heatproof material.
Where localized material doubling is proposed it cannot be assured that the regions of the gas bag first impacted by the hot combustion products are also reliably covered since the protective material may become displaced when being folding in place if it is not connected to the gas bag material. When the material is connected to the gas bag, however, difficulties are experienced in folding in place since the connected material doubling is automatically stiffer than the remaining gas bag material and may in turn result in irregularities when being folding in place so that unprotected material may lie in the region of the primary inflow of hot combustion products. In addition to this the means proposed for flame protection are often very complicated and costly.